Improved apparatus for making acid sulphite of lime



GAMOTIS & MARTIN.

MakingSulphuric Acid.

Patented July 21, 1857. 4

' li'z neuvesn- V i I [KI/67212070.-

' w all, C) Q I N. PETERS. Pholo-Lflhognpher. WJshTngwn, n.6,

. UNITED STATES.

PATE T OF-rrca LAURENT GAMOTIS AND SABIN MARTIN, OF N E\V ORLEANS,LOUISIANA.

'IMPROVED APPARATUS FOR MAKING ACID SULPHITE OF LIME.

Specification forming part of Letters Patent No, 17,830, dated July 21,1857.

To all whom it may concern:

Be it known that we, LAURENT Gnnorrs and SABIN MAJa'rItv, both of NewOrleans, in the State of Louisiana, have invented an Apparatus for theManufacture of Bisulphite of Lime. by Means of. a Vacuum and Suction-Pump; andiwe do hereby declare that the following is a fulland exactdescription thereof, reference being, had to. the accompanying drawings,and to the letters of reference markedthereon... c

. The nature of our invention consistsin 0btaining' bisulphite of limeby means of an apparatus composed of a furnace with a chimney, ofaseries of cisterns or vats, of a, reservoir or aspirating-vat, and ofone or more pumps disposed and worked by combinations difierent fromthose hitherto employed,

To enable others skilled in the art to make and use our invention, wewill proceed to describe its construction, and to render the descriptionof the mode of operation clearer we will first describe ina few wordsthe drawings representing the accompanying model, which drawings give anexternal View of the apparatus, a section of one of its parts, and ahorizontal View.

In Figure l, a a is the furnace; I), retort; c c c, cranks for agitatingthe liquid; (1 d d, taps; h h h, cisterns; K,large cistern foraspirating, and 0 0 0 agitating-paddles.

In Fig. 2, a, 0, represent the furnace; J, furnace-door; e, chimney;ff'fffff, tubes; g g g, funnels d d cl, taps; h h h, cisterns; K, largeaspirating-cistern l, tube with a tap, the length of the tube beingequal to half the height of the cistern K; m, suction-pump, and atopening, with a plug, for the purpose of introducing the water.

In Fig. 3 e is the summit of the chimney; f f fitubes; (,funnel with astop-cock; h h h, the cisterns on a larger scale, and t partitiondividing the upper part of the cistern into two parts or lobes.

The apparatus is constructed in the following manner: furnace andchimney with refracting bricks cemented with a light mortar, covered onthe inside by a concentrated solution of sub-borate of soda, which whenexposed to a great heat forms with the silica of the bricks abonsilicate, leaving on the surface of the bricks a protecting varnishor glaze; the retort in sheet-iron.;'cranks and paddles. in wood; cocks,tubes, and funnels in.

lead; partitionof oak and cisterns of oak also; the staves thick, hoopedwith iron, andcovered on the outside by three or four coatings of oilpaint.

.Mode of proceed mgrdlavin g filled the cisterns h h h with water towithin one-fifth. of the top of the cistern, the level of the Waterbeing about four or five inches above the lower edge of the partition 6'L c', We pour through the funnels g g g a certain quantity of milk oflime, (marble,) we fill the retortb with sulphur, we ignite the sulphur,regulating the supply of atmospheric air by the door of the furnace, soas to admit only sufficient to promote combustion. As soon as thesulphur is ignited the pump m is set in motion, and, the air dilatinginthe cisterns, the pressure of the atmospheric air is able to overcomethe resistance of the several columns of water contained in the immersedtubesffff'ff'f. The suction of the pump m causes the produce ofcombustion to go through the milk of lime contained in the cisterns h hh. Thus carried by the immersed tube f coming from the chimney to thebottom of the corresponding part of the first cistern,the gas risesvertically and, arrived in the first lobe, is received by the tube f andcarried to the bottom of the second half of the same cistern, rises intothe second lobe, whence it is carried successively through the secondand third cisterns by the same mechanism and in the same manner. By thuspassing through the milk of lime the gas combines with it, and thesulphurous acid and lime together form a sulphite of lime at firstinsoluble, but afterward soluble from an excess of sulphurous acid. Thesaturation takes place nearly exclusively in the first two cisterns, andthe third receives but a minute quantity of sulphurous acid. In thecourse of the operation care must be taken to keep the milk of lime inmotion by means of the agitating-paddles. Turning the crank once ortwice now and then suffices.- Nothing reaches the cistern K but azoteand a small quantity of undecomposed-air. When the apparatus has beenworking some time and the bisulphite of lime marks six or eight degrees,we cease pumping, fill with water the cistern K, open the cock Zof theescape-pipe,

nearly closing the furnacedoor to diminish the supply of air, andceasing to move the cranks. As the water escapes the sulphurous acid,arriving slowly, gives the bisulphite one or two degrees more density.We take care during this operation to make use of very cold water,because the capacity of absorption is proportioned to the lowness of thetemperature of the liquid to be saturated. At the same time it is mostessential to avoid, first, introducing too much air into the furnace,because a large quantity of sulphuric acid would be formed, and anexcess of air being introduced would convert the bisulphite intosulphate of lime; second, stirring too often the bisnlphite with thepaddles, because their action being repeated too often is detrimental tothe absorption of sulphurous acid.

The following disposition of the chimney contributes also materially tothe success of the operation. The throat of the chimney is placedseveral inches below the retort. Theai r, then passing over the surfaceof the ignited sulphur, reaches the upper part of the furnace and entersthe chimney, flowing downward. Thus the air is obliged to sweep over thesurface of the sulphur, which takes hold of nearly all the oxygen.Therefore but little undecomposed air passes up the chimney.

The dimensions of this apparatus may be varied according to therequirements of the manufacturer. Any of the known powers may be adaptedto it. The number of the cisterns may be increased and one or more pumpsmay be used. In a small apparatus they can even be dispensed withaltogether; but then it is necessary to have two cisterns instead of thecistern K, their communication to be established or cut off at will bymeans of 'a stop-cock. In order to keep up a continuous action, theseshould be opened alternatively'i. 6., that when one cistern is empty theother is made use of, the first in the meanwhile being refilled. Toproduce the necessary suction, it suffices to let the water contained inone of the cisterns escape. The escape-tube, with a cock Z, Fig. 2,placed under the cistern K, is indispensable. The length of this tube isfor the purpose of emptying the cistern, which were it shorter wouldremain partially or even half full.

To conclude we must add that we have endeavored to render our apparatusas economical as it is simple. One of its principal advantages consistsin producing the suction by means of an aspirating-cistern. Bythisprocess we avoid the contact of the pump with the sulphurous acid, whichcontact has the great inconvenience not only of corrodin g the sides,but also the different pistons, and thus rendering it incapable ofworking.

It may readily be conceived that our pump (being adapted to a cisternwhich receives nothing but azote mixed with a slight quan tity ofundecomposed air, and notin the least exposed to the action of thesulphurous acid, the whole of which has been absorbed during its passagethrough several cisterns containing milk of lime) can be greased atwill. This circumstance causing it to be exempt from the changes anddeteriorations which have proved the greatest obstacle to the success ofthe processes hitherto employed, added to the advantages abovementioned, gives to ourinvention a character of superiority over all theapparatus with which we are acquainted.

Vhat we claim, and desire to secure by Letters Patent, is-

The process of making bisulphite oflime by means of furnace J andcisterns h h h K, operated as set forth in the specification.

L. GAMOTIS. S. MARTIN. \Vitnesses:

L. MERRILL, ll. DANIEL.

